In this paper, the optimization of data link network is studied. Considering the limited resource of data link network in combat environment, data link message transmission needs priority-based queuing processing. In order to improve the efficiency of message transmission and optimize the allocation of network resources, a method of resource allocation of data link network based on genetic algorithm is proposed. In this method, the constraints of resource allocation in data link network are modeled from four aspects: transmission distance, relay or not, network capacity and terminal performance. According to the priority of message transmission, the objective function of maximizing the benefit of message transmission is constructed. Finally, the model function is implemented by using MATLAB. The average benefit and maximum benefit of network resource allocation are obtained by simulation, and the optimal result of network resource allocation is selected as a group of allocation results with the highest output benefit.